WO2005002399A1

WO2005002399A1 - Spring element and support element for a cushion base

Info

Publication number: WO2005002399A1
Application number: PCT/EP2004/006743
Authority: WO
Inventors: Norbert Joswig
Original assignee: Fen Gmbh Schlafsysteme
Priority date: 2003-07-07
Filing date: 2004-06-22
Publication date: 2005-01-13
Also published as: EP1641369A1; DE10330644B3

Abstract

The invention relates to a spring element (1) for a cushion base, comprising a spring body (6) that encompasses several spring tongues (2 to 5) between two support rings (7, 8), said spring tongues (2 to 5) being joined to the support rings (7, 8). Also disclosed is a support element (40) comprising at least one spring element (1), a cover plate (41), and a base element (42). The junction between one respective spring tongue and the support ring is designed such that a straight edge is embodied which forms part of a contour of the support ring while the lateral edges of the spring tongue are free all the way to the straight edge. The straight edges clearly define the force transmission areas for deflecting the applied forces from the support ring into the spring tongues or the spring body while allowing the spring element to be deformed at predefined points and in predetermined directions. In a preferred embodiment, the shape of the contour of the support ring is determined essentially by the straight edges. In an alternative preferred embodiment, the spring tongues adjoin the inner contour of the respective support ring. The inventive spring element and support element are particularly suitable for use in sitting areas and lying areas of upholstered furniture.

Description

SPRING AND SUPPORT ELEMENT FOR A CUSHION BASE

The invention relates to a spring element for a cushion pad with a spring body comprising a plurality of spring tongues between two support rings, the spring tongues passing into the support rings, and a support element with a cover plate, a foot element and at least one spring element.

Spring bodies for cushion pads are known to consist of elastic plastic material and can be compressed in a spring travel directed in the direction of the effective contact force of the loaded cushion pad. The deformation of the spring body can be influenced by its material properties and the design of the spring elements. At the upper or lower ends of the spring body there are generally plate-shaped support rings for fastening the spring body to a foot element or to a cover plate. This overall arrangement then forms a support element for supporting a cushion pad.

EP 0965293 A2 discloses a spring element designed as part of a support for a mattress as a plate spring. The plate spring has several spring plates which can be connected to one another in the region of the edge. The embodiments described there show spring plate elements which are circular in plan and V-shaped in cross section. In order to influence the spring properties, four slots are provided which extend radially from a central opening. The spring plate elements are curved or curved outward in the shape of a shell and merge into a circular support ring at the top and bottom to form a support. This transition from the spring plate to the support ring takes place continuously over the entire circumference of the spring plate. Thus, the sections of the spring plate element which are separated from one another by the slots in the central region of the spring plate element are brought together in the foot or head region outside the slots to form a stable support. With such a curved spring element and the chosen design of the transition into the support ring, high arching stresses can occur in particular in the foot region of the spring element, which can lead to bulging of the spring element. This effect is even more pronounced if the shell shape has small geometric imperfections. This danger also exists in the case of an asymmetrical introduction of force via the support ring directed towards the cushion pad and an overstressing of a section of the arcuate spring element caused thereby. Finally, this can also lead to a buckling or buckling-like bulging out or denting of the overstressed spring element area and thus to a total failure of the spring element.

It is also known from EP 0996349 B1 to design the spring body in the form of narrow web-like spring arms. These start from a base plate, which is used to hold a screw for fastening to the slatted frame, and open into an upper star-shaped, horizontally deformable support plate.

Furthermore, a support element for a cushion pad is known from both of the aforementioned documents, which comprises a cover plate, a foot element and at least one spring element.

Starting from the generic document mentioned in the introduction, the object of the invention is to create a spring element which is designed in such a way that its deformation behavior can be better controlled.

The object is achieved in that the transition of the spring tongue into the support ring is designed such that a straight edge is formed and this forms part of an outline of the support ring and the lateral edges of the spring tongue are free up to the straight edge. With the thus defined transitions of the spring tongues into the support rings and the laterally not held edges of the spring tongues in the area between the support rings, a spring element is created which can suffer a defined deformation at predetermined points when loaded and can be brought back to its original state after its relief , Due to the straight edges, the force transmission areas for deriving the bearing forces from the bearing ring into the spring tongues are clearly defined. Furthermore, with a uniform load on the spring element, the occurrence of arching stresses and thus also the risk of sudden failure can be largely avoided. However, the shape according to the invention also allows asymmetrical or uneven loads on the spring element. The resulting stresses can be due to the horizontal degree of freedom due to the lateral clearance of the edges of the spring tongues are recorded, whereby the inevitably inevitable occurrence of deformations in the form of warping or twisting due to the eccentricity can be kept low. Furthermore, the possibility is also created of having the deformations occur at predefined locations and in predetermined directions.

The term “support ring” used in the context of this invention is understood to mean a ring that is closed or open in the circumferential direction, ring-like frame, plate strips or similar designs of any geometric shape. In addition to the usual circular, arc-shaped, linear and rectangular shapes in sections, this also basically includes shapes in the circumferential direction any linear, non-linear, parallel and non-parallel inner and outer contour lines.

An essential basic idea of the invention can also be seen in the fact that the spring tongues are not connected to one another in the region of the spring body and the spring tongues are only operatively connected to one another via the support rings and in particular their straight edges.

Basically, the spring body comprises at least two spring tongues, which are arranged over the straight edges and preferably lie opposite one another. However, a spring tongue does not necessarily have to be arranged on each straight edge. Additionally arranged rectilinear edges as part of the outline of the support ring without spring tongues connected to it can also only serve to connect the ends of the rectilinear edges equipped with a spring tongue in a straight line to one another, for example in order to create a symmetrical shape of the affected outline of the support ring and thus a better support. and to achieve deformation behavior.

However, one aspect of the invention also provides that the number of straight edges corresponds to the number of spring tongues. If only rectilinear edges are used to form the contour line (with the exception of small fillet areas between the ends of the edges), at least triangular or polygonal contour lines of the support ring are produced, with a spring tongue adjoining each rectilinear edge.

A preferred embodiment consists in that the straight edges are arranged rotationally symmetrically. The axis of rotation runs parallel to the alignment of the spring travel of the spring element, preferably in the vertical direction. As a rule, the length of the straight edge corresponds to the length of the connected end of the spring tongue. The edges can also be longer than the length of the connected end of the spring tongue. The support ring does not necessarily have to be arranged rotationally symmetrically and can also be off-center or at an angle to the direction of the spring travel. In principle, the two support rings do not have to be of identical or similar design in terms of shape, material thickness and choice of material, but in practice it is generally assumed that the design is of the same type.

A further preferred embodiment consists in that the spring tongue adjoins this on an inner contour line of the support ring. In combination with the alignment of the ends of the spring tongues adjoining the straight edges, the force transmission taking place in the area of the edges can be influenced by the support ring in the respective spring tongue and the direction of deformation of the spring element can also be controlled. Due to the connection to the inner contour line, the support line of the support ring formed by the connected spring tongues lies on the inside and thus shortens the clear width between the support points of the support ring.

An advantageous development of the invention also consists in the fact that the shape of the outline of the support ring is essentially determined by the straight edges. Depending on the type of connection, this can affect the outer or inner outline. With the largely rectilinear design of the outline of the support ring, a horizontal spreading ring acting in the plane of the support ring is created. Such a ring anchor also makes it possible to increase the torsional rigidity about the axis of rotation. Only in the transition area of the adjacent ends of the straight edges can there be non-linear connections, such as fillets, for example. This also prevents tears and surface cracks (e.g. hairline cracks) in the corner areas.

The inner contour of the support ring is expediently at least triangular. An equilateral triangle is suitable for increasing the rotational inertia. It is advantageous if the inner contour of the support ring is square. If the edges are also perpendicular to one another, particularly good stiffening of the corner regions is achieved.

In a further expedient embodiment, the outer contour line of the support ring is circular. In this way, loads that attack strongly off-center, as can occur in the corner areas of rectangular support rings, are avoided.

When designing the transition of the spring tongue into the support ring, it is advantageous for this transition to be accordion-shaped. This fold-shaped or zigzag-shaped area can lie in the end region of the spring tongue and / or in the end region of the support ring. As a result, a deformation can be forced at this predetermined point in the region of the straight edges. In order to influence the deformability, these areas can also be formed from a different material than the support ring or the spring tongue. The zigzag-shaped area can be designed on one side on the top or bottom or on both sides like an accordion.

Another preferred embodiment consists in that the spring tongues in the area between the support rings are objected to one another. The decoupling of the spring tongues ensures that no force is transmitted from one spring tongue to the other in the area of the spring body, so that they can deform independently of one another. The spring tongues are thus not operatively connected to one another over the area of the spring body. In this way, curvature and bulging of the spring tongue can be avoided in particular.

The spring tongues expediently have a V-shaped cross section, the angle of the transition between the end of the spring tongue and the support ring being in a range between 120 ° and 150 °. In principle, this angle can be in a range from 90 ° to 180 °. The bends of the spring tongues are preferably directed towards one another inwards. It is also possible for the spring tongues to be linear, undulating, zigzag-shaped, directed inwards or outwards. In addition to the shape and orientation, different materials can also be used for the different spring tongues or support rings. Furthermore, the spring tongues or their sections can have different material thicknesses.

In order to influence the deformation, it also proves advantageous that the cross section of the spring tongue has a taper at least at one point parallel to the straight edge of the spring tongue. As a result, the spring properties can also be adapted to the stresses occurring and the compressibility of the spring element can be increased. These material tapers are preferably provided in the center or in the third points of the developed length of the respective spring tongue.

The object is further achieved for a support element with a cover plate, a foot element and at least one spring element in that the spring element according to the invention is arranged.

In a preferred embodiment of the support element, a plurality of spring elements are stacked one above the other so that the straight edges lie one above the other. The advantageous project Functionally congruent arrangement of the superimposed edges is achieved in that the fastening means provided on the support rings are positioned accordingly. This eliminates the need for time-consuming manual alignment of the adjacent spring elements. Alternatively, the adjacent spring elements can also be arranged such that the edges of the support rings lie one above the other at an angle.

Another preferred embodiment consists in that the foot element is plate-shaped and the spring element rests at least partially on a plate base of the foot element and is held laterally by a plate wall of the foot element. The foot element fixed to a supporting structure (e.g. slatted frame) can therefore absorb both vertical and horizontal support forces. As a result, constrictions of the support ring, which are present, for example, on account of an outer circular and an inner rectangular outline, can be relieved by the plate wall lying over the circumference of the support ring.

When assembling a plurality of support elements forming a support device, the different support elements can have different numbers of spring bodies arranged one above the other and optionally have different spring constants. Furthermore, the spring elements can be stacked one on top of the other in such a way that a progressive spring constant distribution is created.

The usual fastening means can be used for fastening the spring elements to one another and to the cover plate or to the foot element. The arrangement of locking means is particularly suitable here. For example, one support ring has holes for receiving catch elements and the other support ring has elastic projections as catch elements for insertion into the holes of another support ring of a spring element to be connected. In principle, however, other non-positive, positive or frictional connections are also possible. The attachment is secured against rotation and is usually carried out releasably.

With regard to the vibration-damping properties, the individual spring elements and also the individual spring tongues can be designed to have different levels of damping. For example, the legs of the spring tongues directed towards the upper support ring can be damped less than the legs directed towards the lower support ring. This results in a stiffer spring effect with increasing load. Plastic, in particular elastomer, is used as the material, for example applies. The one-piece or multi-part spring element is produced by the known methods for processing plastics.

The invention is furthermore also suitable for forming a support device for a cushion pad with a plurality of support elements according to the invention, these being arranged at a distance from one another. The arrangement of the support elements is adapted, among other things, to the shape of the cushion pad or to the level of the load to be absorbed. The support elements can have a different number of spring bodies arranged one above the other and / or can be equipped with different spring constants. Adjacent support elements of the support device should in particular be arranged in such a way that the cover plates of adjacent support elements do not engage behind.

The spring element, support element and the device provided in the invention are particularly suitable for seating or lying surfaces and furniture devices provided therefor.

The invention is explained in more detail below on the basis of a preferred exemplary embodiment with reference to the drawings. They show schematically:

1 shows a partially sectioned perspective view of a spring element in an undeformed state; and

2 shows a cross section of a support element with a cover plate, a foot element and three spring elements according to the invention in an undeformed state; and

3 shows a partially sectioned perspective view of the foot element from FIG. 2.

1 shows a partially sectioned perspective view of a spring element 1 with a spring body 6 between two support rings 7 and 8. The spring body 6 comprises a total of four V-shaped spring tongues 2 to 5. In addition to the spring tongue 3 shown completely, the spring tongues 2 adjacent to it are and 4 for better illustration of the spring element 1 shown in section. The two remaining parts of the spring tongues 2 and 4 and the spring tongue 5 opposite the spring tongue 3 are not shown. The sectional plane runs perpendicularly with respect to the horizontally aligned support rings 7 and 8, as a result of which only one half of the spring element 1 can be seen. The spring element 1 is rotationally symmetrical to an axis of rotation 55, which is in the center runs between the spring tongues 2 to 5 and perpendicular to the horizontally aligned support rings 7 and 8 (see FIG. 2).

According to the invention, the transition of each spring tongue 2 to 5 into the upper bearing ring 7 is designed such that a straight edge 9 to 12 is formed in each case. The edge 12 or spring tongue 5, which cannot be seen in FIG. 1, is symmetrical to the cutting plane with respect to the edge 10 or spring tongue 3. This configuration of the transition between the spring tongues 2 to 5 and the support ring 7 is correspondingly adopted in the transitions of the spring tongue 2 to 5 in the lower support ring 8, so that the straight edges 9 ', 10', 11 'and 12' are formed there , The edges 9 to 12 and 9 'to 12' are each of the same length and are arranged rotationally symmetrically.

To avoid repetitions, the components and their modes of operation of the embodiment shown in FIG. 1 are exemplarily explained below as a rule only on a spring tongue, a support ring or a straight edge, etc. Due to the rotationally symmetrical shape of the spring element, the non-visible components can also be easily recognized from the perspective view. It is pointed out that the explanations for one of several existing components also apply in principle to the other components.

The straight edges 9 to 12 defined above essentially determine the shape of an inner contour line 14 of the support ring 7. This has a rectangular shape and thus edges 9 to 12 which are of equal length and perpendicular to one another. An outer contour line 13 of the support ring 7 is arranged in a circle around the axis of rotation 55. Alternatively, it would also be possible to make the outer contour line 13 rectangular and at the same time to make the inner contour line 14 circular and to have the spring tongues 2 to 5 connected to the outer contour line 13 of the upper support ring 7 with the formation of straight edges. Accordingly, the inner contour line 14 'or the outer contour line 13' of the lower support ring 8, which includes the straight edges 9 'to 12', is designed.

The lateral edges 16 and 17 of the spring tongue 3 are free in the area between the support rings 7 and 8, ie in the area of the spring body 6, up to the straight edges 10 and 10 '. The spring tongue 3 is thus in the area of the spring body 6 neither directly nor indirectly with the other spring tongues 2, 4 and 5 in operative connection or held laterally (ie horizontally) by other means. An active connection between the spring tongues 2 to 5 only exists via the support rings 7 and 8. Between the rectilinear edges 9 and 10 or 10 and 11, fillets 24 and 25 are provided, which on the one hand serve to allow slots 22 and 23 to emanate from the corner regions between edges 9 and 10 or 10 and 11 which meet run continuously along the development of the spring body 6 to the opposite corner area between the straight edges 9 'and 10' or 10 'and 11'. On the other hand, the fillets 24 and 25 are also suitable for preventing the support ring 7 from tearing open as a result of any local stress peaks or fatigue cracks in the long-term behavior.

The lateral clearance of the edges of the spring tongues can also be described in the present embodiment in that the spring body 6 has four slots 22, 23 and 28, 29 which extend radially and over its entire height from the support ring 7 to the support ring 8, as a result of which the four spring tongues 2 to 5 are formed. It is essential that the slots 22, 23, 28, 29 run continuously over the entire development of the spring body cross section. As shown, these slots 22, 23, 28, 29 preferably extend from the corner regions of the inner outline 14 and 14 '.

The spring tongues 2 to 5 have a double V-shaped cross section, i.e. they are V-shaped with respect to the sectional plane and the horizontal plane, the buckles 21 of which are directed inwards and lie opposite one another. The inside angle between the support ring lying in the horizontal plane and the upper connecting leg of the spring tongue 2 is approximately 150 °.

Likewise, with regard to the transition of the spring tongues into the respective support ring (for example spring tongue 2 in the transition to support ring 7), it can also be seen from FIG. 1 that it can be designed in the form of a fold or accordion. The thinning of the material that is partially present specifies the point at which a defined deformation is to take place or at which point the load acting on the bearing ring 7 is to be introduced into the spring tongue 2. This linear or selective reduction of the streaking is provided (at predetermined points) in order to be able to control the location and the direction of the deformation of the spring element. The fold-shaped design of the end region of the spring tongues 2 to 5 can be designed not only on one side as shown, but also on both sides (e.g. accordion-like) and on both ends of the spring tongue.

As a further measure for influencing the deformation of the spring element 1, a material taper 19 of the spring tongue 2 is formed approximately in the middle of the upper leg of the V-shaped spring tongue 2 parallel to the straight edge 9. To fasten several spring elements 1 one above the other, snap-in connections are provided. For this purpose, the upper support ring contains 7 holes 26 and the lower support ring 8 elastic projections 27 for receiving and snapping into corresponding holes 26 of a further spring element 1 arranged below. Of course, the holes 26 can also be in the lower support ring 8 and the projections 27 on the upper Support ring may be provided. Alternatively, other positive, non-positive or frictional connection types are possible.

Fig. 2 shows a cross section through a support element 40 with three spring elements 1 arranged one above the other, a cover plate 41 for supporting upholstery and a foot element 42 for fastening the support element 40 to a supporting structure (e.g. slatted frame) of a piece of seating or reclining furniture. The three spring elements 1 are fastened to one another by means of the latching means already described in the form of holes 26 and projections 27 which engage in a latch-like manner. To fasten the spring column formed from the three spring elements 1, the foot element 42 also has a ring 53 with holes 47, into which the projections 27 of the lowest spring element snap (see also FIG. 3).

The uppermost spring element 1 is also connected to the cover plate 41 by a snap mechanism, the upper bearing ring 7 of the uppermost spring element 1 again having holes 26. In this case, projections 54 engaging in the holes 26 are arranged on a fastening ring 52 formed as part of the cover plate 41. This fastening ring 52 runs below the support plane of the cushion pad and has a U-shaped cross section. This is followed by stiffening ribs 51 running parallel to the cover plate 41, which extend up to an outer edge 50 of the cover plate 41 which is bent almost vertically downwards. The stripping ribs 51 and the edge 50 are provided in order to stiffen the cross section of the cover plate 41 weakened by ventilation holes 48.

The plate-shaped foot element 42 shown in FIG. 3 comprises a plate bottom 43 with a plate wall 44 adjoining it vertically, which merges into a horizontally oriented ring 53 parallel to the plate bottom 43. This ring 53 has a plurality of holes 47 for receiving the projections 25 of a spring element 1. There is also the possibility of at least partially placing a spring column arranged from a plurality of spring elements 1 on the plate base 43, in order thereby to enable the spring column to be held laterally by the plate wall 44. The plate base 43 has a central hole 46 for fastening the support element 40 and two cylindrical hollow cross-section-shaped pins 45 in the outer region of the plate base 43 for receiving screws or similar fastening means. As a result, the foot element 42 and thus the support element 40 can be fixed to a supporting structure of the cushion pad.

Claims

1. Spring element (1) for an upholstery pad with a spring body (6) comprising a plurality of spring tongues (2 to 5) between two bearing rings (7, 8), the spring tongues (2 to 5) passing into the bearing rings (7, 8), characterized in that the transition of the spring tongue (2 to 5) into the support ring (7, 8) is designed such that a straight edge (9 to 12, 9 'to 12') is formed and this part of an outline ( 13, 14, 13 ', 14') of the support ring (7, 8) and the lateral edges of the spring tongue (2 to 5) up to the straight edge (9 to 12, 9 'to 12') are free.

2. Spring element according to claim 1, characterized in that the straight edges (9 to 12, 9 'to 12') are arranged rotationally symmetrically.

3. Spring element according to claim 1 or 2, characterized in that the spring tongue (2 to 5) on an inner contour line (14, 14 ') of the support ring (7, 8) adjoins this.

4. Spring element according to one of the preceding claims, characterized in that the shape of the outline (13, 14, 13 ', 14') of the support ring (7, 8) essentially from the straight edges (9 to 12, 9 'to 12 ') is determined.

5. Spring element according to one of the preceding claims, characterized in that the inner contour line (14, 14 ') of the support ring (7, 8) is at least triangular.

6. Spring element according to claim 5, characterized in that the inner contour line (14, 14 ') of the support ring (7, 8) is square.

7. Spring element according to one of the preceding claims, characterized in that the outer contour line (13, 13 ') of the support ring (7, 8) is circular.

8. Spring element according to one of the preceding claims, characterized in that the transition of the spring tongue (2 to 5) in the support ring (7, 8) is accordion-shaped.

9. Spring element according to one of the preceding claims, characterized in that the spring tongues (2 to 5) in the region between the support rings (7, 8) are spaced apart.

10. Spring element according to one of the preceding claims, characterized in that the spring tongues (2 to 5) have a V-shaped cross section, the angle of the transition between the end of the spring tongue (2 to 5) and the support ring (7, 8) is in a range between 120 ° and 150 °.

11. Spring element according to one of the preceding claims, characterized in that the cross section of the spring tongue (2 to 5) has at least at one point a taper (19) parallel to the straight edge (9 to 12) of the spring tongue (2 to 5).

12. support element (40) for a cushion pad with a cover plate (41), a foot element (42) and at least one spring element (1) according to claim 1.

13. support element according to claim 12, characterized in that a plurality of spring elements (1) are stacked one above the other so that the straight edges (9 to 12) lie one above the other.

14. Support element according to claim 12 or 13, characterized in that the foot element (42) is plate-like and the spring element (1) at least partially rests on a plate base (43) of the foot element (42) and from a plate wall (44) of the foot element (42) is held laterally.